Sand blast machine



May 17, 1932;

R. RUEMELIN SAND BLAST MACHINE Filed July 26. 1926 3 Sheets-Sheet 1 May17, 1932. R. RUEMELIN SAND BLAST MACHINE Filed July 26. 1926 5sheets-sheet 2 N Z wE N MW V U T NR 7 wp M mQV R 9. a

May 17, 1932.

R. RUEMELIN SAND BLAST MACHINE Filed'July 26. 1925 IiSheets-Sheet a I II I I I lip: I;

Patented May 17, 1932 UNITED STATES PATENT orrlca Application filed July26, 1926. Serial No. 124,979.

This invention relates to new and useful im rovements in sand blastmachines, and an ob ect of the invention is to provide such a machine ofhigh power, yet flexible and simple in operation, thereby adapting itfor practically all kinds of sand blasting, ranging from light frostingto deep lettering in .such material, as granite, utilized for monuments,corner-stones, and the like.

A further object of the invention is to provide a sand blast machinehaving a sand control valve comprising a readily replaceable rubbervalve and seat, thereby eliminatin unnecessary wear and repairs, asrubber o l5 fers a greater resistance to the abrasive action of flowingsand than other materials.

A further object is to provide a sand blast machine, comprising a sandvalve and an air valve, and means provided within the sand 29 valvewhereby, when said valve has once been adjusted for the proper mixtureof sand and air for a given work, the entire control of the machine willbe accomplished by the manipulation of the air valve only, therebygreatly increasing production.

A further object is to provide such an apparatus having means forautomatically cutting oil the supply of sand from the tank, when the airvalve is shut off, thereby positively preventing an excess quantity ofsand from entering the hose, which usually results in the obstruction ofthe passage therethrough.

Other objects of the invention are to provide a sand blast machinehaving; a sand box or chamber in which is mounted a removable bushingwhich may be quickly and cheaply replaced when necessary; a three-wayair control valve having a flat seat adapted to withstand long servicewithout leakage; a direct flow of sand and air, thereby reducingfriction and wear, and also making available the full force of theblast; a clean-out plug of ample size accessibly located in the bottomof the tank, thereby permitting the latter to be quickly emptied ofsand; a removable cleanout cover mounted upon the sand valve wherebyaccess may readily be hadto the interior thereof for cleaning and otherpurposes; a large drier having means therein for confined to the exactfeatures shown, as varie5 ous changes may be made within the scope ofthe claims which follow.

In the accompanying drawings,

Figure 1 is an elevational view showing till? general construction ofthe improved ma- 0 me;

Figure 2 is a plan view of Figure 1;

Figure 3 is an enlarged detail sectional view on the lines 33 of Figures2 and 4, showing the position of the sand in the sand valve, when theapparatus is inoperative;

Figure 4 is a detail sectional view on the line H of Figure 3, showingthe removable bushing in the sand box or chamber;

Figure 5 is a detail sectional view on the line 5-5 of Figure 2, showingthe air control valve in operative position;

Figure 6 is a similar view showing the air valve in inoperativeposition;

Fi re 7 is a detail sectional view on the line -7 of Figure 2, showingthe interior of the drier;

Figure 8 is a detail view, partially in section, of a portion of the airfiltering tube within the drier;

Figure 9 is a cross-sectional view on the line 99 of Figure 8;

Figure 10 illustrates a modified form of air-filtering tube; and

Figure 11 is a cross-sectional view on the line 1111 of Figure 10.

The novel sand blast machine featured in this invention comprises a tank12 adapted to contain sand 13, such as is usually employed in connectionwith machines of this kind.

The tank 12 is supported upon legs 14 secured thereto by such means aswelding. A filler opening and cap 15 is provided in the upper portion ofthe tank for the introduction of the sand.

A sand outlet 16 is provided in the bottom of the tank 12 and issurrounded by a flange 17 to which is secured an air and sand mixingdevice comprising a casing 18 secured there to by bolts 19. A passage 21is provided in the upper portion of the casing 18 and terminates with anannular extension 22, having a flexible sleeve 23 mounted exteriorlythereof toprovide an annular valve seat. A valve 24, also of flexiblematerial, is secured to a member 25 fixedly mounted upon a shaft 26,rotatably mounted in bearings provided in the upper portion of thecasing 18 as particularly shown in Figure 4. The valve seat or sleeve 23and the valve 24 are preferably of rubber, which has been found, inactual practice, to offer a greater resistance, than other materials, tothe abrasive action of the sand in passing through the valve during the.operation of the apparatus.

A partition 27 is provided in the casing 18 immediately below the sandvalve to form an air and sand mixing chamber 28 in the lower portion ofthe casing 18, as shown in Figures 3 and 4. An orifice 29 establishescommunication between the valve chamber and the mixing chamber 28. Oneside of the casing 18 has a cover 31 removably secured thereto wherebyaccess may be had to the interior of the valve chamber and mixingchamber for cleaning and other purposes.

The mixing chamber 28 is provided with a flanged extension 32 having abushing 33 removablv mounted therein as shown in Figure 4. 'This bushingis provided with a tapered bore 34 which functions to guide the mixtureof sand and air from the chamber 28 into a nipple 35 secured to theflanged extension 32 by means of a ring 36 and bolts 37. This bushingalso protects the casing against wear. The nipple 35 is preferablyprovided with an enlarged head 38 having a threaded engagement with thering 36. The usual operating hose 39 has one end secured to the nipple35 and the usual nozzle 41 mounted in the opposite end thereof. Thisnozzle, of course, is' interchangeable depending upon the type of workbeing performed.

The sand valve 24 is controlled bV means of a lever 42 terminallysecured to the shaft 26, and having a lock screw 43 mounted in the upperportion thereof adapted to engage a quadrant 44 to lock the lever in itsadjusted positions. Bv the manipulation of the lever 42, the supply ofsand to the mixing chamber 28 may be controlled, and, if desired, theflow of sand from the tank 12 may be completely out off by moving thevalve into closing position.

Air is supplied to the mixing chamber 28 throu h a pipe 45 having itsupper end connecte to an air control valve 46 shown in Figures 1, 5 and6. A valve 40, of ordinary construction, is interposed in the pipe 45whereby communication may be cut off between the mixing chamber and aircontrol valve.

The air valve is shown in detail in Figures 5 and 6. It will be noted byreference to these figures, that the air pipe 45 is connected to thebase 47 of the valve 46. A pipe 48 also has one end connected to thebase 47 of the air valve, and has its other end connected to the upperportion of the sand tank 12, as indicated at 49 in Figure 1. The upperportion 51 of the air valve is secured to the base 47 by means of bolts52, and provides an air chamber 53 having an air supply pipe 54 leadingtherefrom to an air drier which will subsequently be described. A slide55 is mounted within the air chamber 53 and functions toopen and closethe ports 56, 57 and 58, communicating respectively with the pipes 45,48 and 59, the latter being the exhaust of the valve, as shown in Figure5. A passage 61 is provided in the slide 55 adapted to be moved intoregistration with the port 57 when the valve is in operative position.When thus positioned, it will be noted that the exhaust port 58 will beclosed. A recess 62 is also provided in the slide 55 adapted to bridgethe ports 57 and 58 when the slide is positioned as shown in Figure 6.When thus positioned, the supply of air from the chamber 53 will be outOK from the pipes 45 and 48, and the air confined within the pipe 48,and therefore the tank 12, will be exhausted to the atmosphere, asindicated by the arrows in Figure 6. The slide valve 55 is retained uponits seat upon the upper face of the base 4'; by the air pressure in thevalve chamber 5 The means provided for actuating the slide valve 55consists of an operating lever 63 terminally secured to a shaft 64mounted in bearings provided in the upper portion 51 of the valve asshown in Figures 5 and 6. A depending arm 65 is secured to the shaft 64and has its lower end engaging the slide valve 55, whereby actuation ofthe arm 65 will cause the slide valve 55 to be reeiprocated upon itsseat as shown in Figures 5 and 6.

A feature of this invention resides in the novel means provided forthoroughly drying the air and removing all moisture therefrom beforebeing delivered to the sand and air mixing chamber 28. Such meanspreferably consists in the provision of an air drying tank 66 having aconnection with the air valve 46 by means of the pipe 54, connected tothe upper wall thereof as shown in Figure 7 The drier tank 66 has aconnection with a source of air supply through a pipe 67 having ashut-off valve 68 interposed therein, as shown in Figure 1. A flangedopening 69 is rovided in the up er wall of the tank6 6, and has athreaded ug 71 mounted therein in which one end the air supply pipe 67is secured as shown. A cylindrical member 72 is securedto the plug 71and depends into the drier tank 66 to approximately one-half the lengthof the tank. A nipple 73 of substantially the same diameter'as thesupply pipe 67 is also secured to the plug 71 preferably in axialalignment with the pipe 67 and cylindrical member 72, thus rovlding anannular space 74 bet-ween the mpple 73 and the wall of the member 72.Portions of the nipple 73 are cut away intermediate its ends, and withinthe cylindrical member 72, as indicated at 7 5-7 5. A perforated plateor sleeve 76 is mounted upon the exterior of the nipple 73 to cover thecutaway portions 75 as particularly shown in Figures 8 and 9. Thisperforated plate or sleeve 76 may be secured to the nipple by screws 77.A cap 78 is provided upon the lower end of the nipple 73 torestrict thepassage of air therethrough. A small duct 79, however, is providedtherein to permit water, tending to accumulate therein fromcondensation, to be precipitated into the bottom of the drier tank asshown in Figure 7. A pressure gauge 81 is preferably mounted in theupper wall of the drier tank to indicate the ressure therein.

In the operation 0 this novel sand blasting machine, the air controllever 63 may be moved from the position shown in Figure 6 to that shownin Figure 5, wherein it will be noted that the supply of air from thepipe 54 will flow through the chamber 53 and into the pipes 45 and 48.Circulation through the pipe 48, however, will be substantiallyinterrupted as soon as the pressure in the upper portion of the sandtank 12 reaches the pressure inthe air chamber 53. Air circulationthrough the pipe however, will continue as long as the slide 55 of theair valve is in the position shown in Figure 5, thereby de 45 liveringair under pressure to the sand and air mixing chamber 28 with theresultant blowing of the sand therefrom into the hose 39, and throughthe discharge nozzle 41. During the initial operation of the apparatus,

the sand control valve 24 will be regulated by means of the lever 42until the proper mixture of sand and air is obtained, after which thelever 42 may be locked in such position by means of the lock screw 43,and thereafter the entire operation of the machine will be controlled bymanipulation of the air control lever 63.

When the apparatus is inactive, as shown in Figure 3, the sand will pileup in the mixing chamber 28 in the form of a cone, thereby interruptingthe flow of sand from the tank 12 without closing the valve 24, and alsopreventing the sand from entering the nipple 35,.

and therefore the hose 39, with its attendant troubles, such asobstructing the passage therethrough. As soon as the air control valveis initially moved into operative position, the flow of air from thepipe 45 into the mixing chamber 28 will be comparatively slow as aresult of the accumulation of sand in the hose 39, caused by the mixtureof sand and air remaining therein when the supply of air to the mixingchamber 28 was cut ofi.-

Upon the initial starting of the apparatus, however, the pressure builtup in the hose 39 will cause the sand accumulated therein to be blowntherefrom, after which the velocity of the air from the pipe 45 throughthe chamber 28 will increase to the extent that thecolumn of air passingthrough the chamber 28, will remove the upper portion of the sand conedisposed therein, after which a constant-mixture of sand and air will bedelivered to the hose 39, depending upon the position of the sand valve24. Therefore, when the apparatus is inactive a quantity of sand willremain in the bottom of the mixing chamber 28 as indicated by the dottedlines in Figure 4. The shape of the mixing chamber 28 is such as toprovide ample passage for the air around the sand cone disposed thereinupon initial starting of the apparatus, as clearly shown in Figure 3.

The function of the drying tank 66 is to thoroughly dry the air andremove all moisture therefrom before being delivered to the mixingchamber 28, as hereinbefore stated. The air delivered to the drier tank66 from the pipe 67 is discharged into the nipple 73 under pressure froma compressor or other suitable source of air supply under pressure. Fromthe nipple 73 it is discharged through the small orifices in theperforated plate 76, and into the annular space 74 between the nippleand the cylindrical member 72. As it is discharged from the nipple, itimpinges against the wall of the member 72 and expands and cools, andany moisture contained therein will be precpitated to the bottom of thetank, as clearly shown in Figure 7. Any moisture accumulating in thelower end of the nipple 73 will be discharged through the orifice 7 9into the bottom of the tank as also shown in this figure. From the tank66, the air is delivered through the pipe 54 to the air chamber 53provided in the air control valve, shown in Figures 5 and 6. Thus allair delivered to the air valve 46 will be thoroughly dried beforeentering the chamber 53. A drain cock is provided in the lower wall ofthe drier tank 66 whereby the water accumulating therein may be drainedtherefrom.

A clean-out plug 82 is preferably provided in the casing 18 of the sandvalve 24 as shown in Figure 3. By the removal ofthis plug, sandaccumulating in the discharge passage 16 of the tank, may readily bedislodged therefrom by the insertion of a rod or suit- I provided at theupper end of the sand tank.

The general construction and arrangement of the parts of this novel sandblasting machine is such that it will readily lend itself for use forpractically all kinds of sand blasting. It is operable by means of asingle control lever, and by means of the sand valve 24,

the flow of sand from the tank 12 to the mixing chamber 28 may readilybe controlled to obtain the proper mixture of sand and air for variouskinds of work. After thesand valve has been adjusted to produce theproper mixture for a given work, the lever 42 of the sand valve may belocked in such adjusted position by means of the lock screw 43, afterwhich it will only be necessary to operate the air control valve lever63. The construction of the air valve is such that the mixture of sandand air, discharged from the nozzle 41 of the hose 39, may be used forwork ranging from light frosting to deep lettering.

In Figures 10 and 11, there is shown a drier tank nipple of modifiedconstruction. This nipple is composed of a series of circular members83, each having a central hub 84 supported by arms 85 as shown in Figure11. The upper section 86 has a. cylindrical extension 87 terminallythreaded whereby it may be secured to the plug 71 in a manner similar tothe nipple 73. The lower terminal section 88 of the device functionsas acap and has a small orifice 89 therein through which water accumulatingtherein may be precipitated into the lower portion of the tank in amanner similar to that shown and described with reference to Figure 7.The hubs 84 of the members 83 and sections 86 and 88 are apertured toreceive a tie rod 90 whereby the sections may be securely tied togetheras shown in Figure 10. The hubs 84 of the various members are of suchlengths as to slightly space the members apart, thereby provid ingannular gaps therebetween through which the air under pressure isdischarged therefrom into the relatively larger cylindrical member 72.

The opening 29 is only completely filled with sand at the time that thevalve 24 is fully opened, and this service is only required for a mildcutting action, as for tracing or frosting on glass. For hard cuttingaction, the valve 24 is only partly opened so that only a small amountof sand is draining through the opening 29. During the blastingoperation, the sand is practically removed from the chamber, as fast asdelivered. No pile of any substantial size is therefore being formed atthis time. .When air supply to the mixing chamber is shut ofi, the sandcontinues to pass through the valve 24 and opening 29 thus forming afrustro-conical pile in chamber 28 as shown in Figure 3. When the air isagain turned on the hose 35 may be obstructed, and it is thereforenecessary to remove that obstruction before the proper sand blastoperation can be efiected. In order to remove the obstruction in thehose 35, the air pressure can be built up (in the chamber around thesand pile) to discharge all-of the accumulated sand in the hose beforemore sand from the pile enters the hose. When the obstruction isremoved, the air has a free flow under full velocity across the pile,and by a whisking action; be inning substantially at the top of the pie, gradually substantially removes the pile, and thereafter -sionthrough which the opening 29 passes,

because the velocity of the air would be considerably reduced. Moreover,the cross-sectional area of the pipe 45 is considerably less than thecorresponding area of the sand pile, the apex of which pile is opposedto it.

The valve is never shut when machine operation is discontinued. Theresult is. that after the machine stops operating the cone of sand isformed.

In the event that the hose 35 is unobstructed by sand, then the airflows directly from pipe 45 to the hose 35 and first Whisks away thesand which had been formed in a cone at the last stopping of themachine. It is very important in order to prevent the loss of availableforce in the air that the air has a direct flow from the pipe 45 to thehose 35. It is also important that the. air meet with no obstructionwhen starting. It is for this reason that the pipe 45 is positioned nearthe top of the sand cone. It would be objectionable to position the pipe45 at the bottom of the sand cone on account ofthe greater resistance inforcing the air through the thick body of sand. Therefore, experiencehas taught that if after the formation of a cone, the air is turned onand is directed to the middle or to the bottom of the pile, there ismore tendency for the hose 35 to plug. Therefore, herein the air iscaused to act directly principally at the top portion of the cone.instead of at some lower level. By application of the air near the apexof the cone, the

less than that of the pipes 3539. It is for this reason that it is veryimportant not to deliver sand in excess at the beginning when the coneis broken due to the initial introduction of air, because the air is atthat time carrying away part of the sand of the cone, and part of thesand is being delivered through opening 29, and thus there is .a smallsurcharge delivery of sand. However, as the operation proceeds the coneof sand is gradually removed.

In initially removing the sand by directing the blast at the bottom ofthe pile, it takes more time to remove the surplus, while when the blastis directed at the top of the cone, the action at the nozzle is quickerbecause of the smaller quantity being taken ofi of the accumulated pile.There is a time period between the starting of the apparatus, and normalrunning. By normal running is meant the highest efliciency of blast.There is a sacrifice in blast while the sulplus sand is being removed,and this sacrifice is less as a matter of fact when the air is appliedat substantially the thinnest portion of the'pile. In all other types ofmachines known to me, it is necessary to shut off the supply of sandsage horizontally leading into said chamber, and aligned with saidnozzle passage, a vertical opening below the valve establishingcommunication between the valve chamber and the mixing chamber to form asand cone in the mixing chamber in line with the passages, the size ofthe mixing chamber being such that air currents may pass either throughthe cone or on each side of it during movement towards the nozzlepassage.

In witness whereof, I have hereunto set my hand this 19th day of July1926.

RICHARD RUEISELINL before turning on the air in order-to clean out themixing chamber 28.

I claim as my invention:

1. A sand tank, a valve casing attached to the tank and having an uppervalve chamber and a lower mixing chamber, and passages respectivelyestablishing communication between the tank and valve chamber, and valveand mixing chambers, a pipe line communicating across the mixing chamberbeneath the latter passage at a level intermediate the top and bottom ofthe chamber, a valve inthe upper chamber adapted to close the firstmentioned passage, both chambers being open at one side, and a plateremovably closing the chambers and allowing simultaneous access to both,when removed.

2. A sand tank havin a valve casing having an upper valve cham er, and alower mixing chamber, passages respectively establishing communicationbetween the tank and valve chamber and valve and mixing chamber, a valvein the upper chamber adapted to close the first mentioned passage, bothchambers being open at one slde, and a plate removably closing thechambers and "allowing simultaneous access to both, when removed.

3. A sand tank having a circular outlet opening at its bottom, a valvechamber into which said opening delivers, a tubular valve seat of rubberin said valve chamber forming an extension of said opening, a swingingsemi- (pherical rubber valve having its spherical si e cooperative withsaid tubular seat to control sand flow, a mixing chamber directl y belowthe valve chamber, said chamber havmg a nozzle passage leadinghorizontally therefrom, and having a compressed air pas-

